Flotation separation of glaserite from sodium chloride and other salts

ABSTRACT

Glaserite is selectively separated from glaserite-sodium chloride-potassium chloride salt complexes by froth flotation using as the reagent fatty acids or their salts, hydrocarbon sulfates or hydrocarbon sulfonates.

United States Patent Chemtob et al.

[451 July 11, 1972 [54] FLOTATION SEPARATION OF [72} inventors: Elie M. Chemtob, Ciaremont; William R. White, Alta Loma; Rolando V. Mar-cote, La Verne, all of Calif.

[73] Assignee: Occidental Petroleum Corporation, Los

Angeies, Calif,

[22] Filed: Aug. 6, 1969 [2!] Appl. No.: 848,092

[52] US. Cl. ..209/l66 [51] Int. Cl ..B03d 1/02 [58] Field of Search ..209/ l 66; 23/ l 21 [56] References Cited UNITED STATES PATENTS U A 7 1,678,312 7/1928 Adams ..209/l66 X GLASERITE FROM SODIUM CHLORIDE AND OTHER SALTS J. Appl. Chem. (USSR) 12, 38 l- 387, i939 Kuzln Gaudin, Flotation, McGraw-Hiil, 1957 pg. 522

Primary Examiner-Frank W. Lutter Assistant Examiner-Robert Halper Attorney-Christie, Parker & Hale ABSTRACT Glaserite is selectively separated from giaserite-sodium chloride-potassium chloride salt complexes by froth flotation using as the reagent fatty acids or their salts, hydrocarbon sulfates or hydrocarbon suifonates.

4Claims,No Drawings FLOTATION SEPARATION OF GLASERITE FROM SODIUM CHLORIDE AND OTHER SALTS BACKGROUND OF THE INVENTION The mineral glaserite (3K SO -Na SO,) or aphthitalite, as it is sometimes called, is an important source of potassium sulfate (K 80 This mineral is found in various areas throughout the world in subsurface ore deposits, playa deposits, fumarole deposits, as well as complex brines such as the Searles Lake brine.

1n the evaporation of brines it is extremely difficult to recover glaserite from a salt harvest by fractional crystallization because the phase relationships controlling the respective solubilities of the components of potassium-sodium-sulfatechloride brines are unfavorable for complete isolation of glaserite. What processing is available requires multisteps involving high energy consumption and high capital and operating expenditures. As a result of this, glaserite has long been ignored as a recoverable salt value.

With the cost of ore processing increasing, it has become economically important to recover glaserite.

SUMMARY OF THE INVENTION It has now been found that glaserite can be selectively separated from salt complexes using conventional froth flotation equipment and processes when there is used as the collector reagent straight chain fatty acids and their salts, saturated or unsaturated hydrocarbon sulfonates and saturated or unsaturated sulfates.

DESCRIPTION According to the present invention glaserite is separated from a salt complex using fatty acids and their salts, hydrocarbon sulfonates or hydrocarbon sulfates.

The fatty acids used as the collector reagent in the practice of this invention are saturated and unsaturated straight chain fatty acids containing from about 5 to about 22 or more, preferably from about 16 to about 20, carbon atoms in the chain. Illustrative, but nowise a limiting of the fatty acids which may be used in the practice of this invention, are caprylic, lauric, myristic, palmitic, stearic, oleic, linoleic, linolenic, arachidic, behenic, tall oil and like fatty acids. The fatty acids may be used in a purified state or in a crude state as a mixture.

The fatty acid salts used in the practice of this invention are normally obtained by the neutralization of the crude fatty acids with sodium hydroxide, potassium hydroxide, ammonia and like bases.

When used as the reagent collector for glaserite, the quantity of fatty acids or fatty acid salts used is not narrowly critical and can generally range from about 50 to about 1,000, preferably from about 150 to about 500, grams per ton of ore solids processed.

The sulfonated hydrocarbons useful in the practice of this invention generally include, among others, sulfonated olefins and alkane sulfonates. The sulfonated olefins are generally obtained by the sulfonation of olefins, preferably the a-olefins, containing at least five carbon atoms with sulfur trioxide. Some techniques of their preparation are more particularly set forth in British Pat. No. 983,056 and French Pat. No. 1,419,652, incorporated herein by reference. Useful, but nowise a limiting of the olefins which may be sulfonated for use in the practice of this invention, are the pentenes, hexenes, heptenes, octenes, nonenes, decenes, undecenes, dodecenes, tridecenes, tetradecenes, pentadecenes, hexadecenes, octadecenes, nondecenes, eicosenes, heneicosenes, doeicosenes, trieicosenes, tetraeicosenes, pentaeicosenes, hexaeicosenes, octaeicosenes and like olefins, as well as mixtures thereof. As indicated, sulfonated olefins should contain at least five, preferably 16 to 30, and more preferably from about 20 to about 26 carbon atoms in the chain.

Based on the same group of olefins described above, the alkane sulfonates are obtained by reacting the corresponding olefin with an alkaline bisulfite under free radical conditions,

as more particularly set forth, for instance, in U.S. Pat. Nos. 2,653,970, 3,084,186 and 3,168,555, which are incorporated herein by reference. The alkane sulfonates, based on aolefins, may also be prepared by the addition of hydrogen sulfide to an a-olefin to give a mercaptan followed by oxidation to the sulfonate; the addition of a-olefins to thioacetic acid to give a thioester, which is then oxidized to the sulfonate; and the addition of hydrogen bromide to the a-olefln to give an alkyl bromide, which is converted to a sulfate by the addition of sodium sulfite. As with the sulfonated a-olefins, the alkane sulfonates should contain at least five, preferably from about 10 to 30, carbon atoms.

The hydrocarbon sulfates used in the practice of this invention are typically prepared, as is known to the art, by the reaction of unsaturated hydrocarbons, such as unsaturated petroleum fractions, olefins, with a-oleflns being preferred, and unsaturated fatty acids with sulfuric acid under mild conditions. Useful sulfates are prepared from unsaturated petroleum fractions containing at least five carbon atoms and from the olefinsand fatty acids defined above. The preferred sulfated hydrocarbons contain from about 12 to about 30 carbon atoms, more preferably from about 16 to about 26 carbon atoms.

The hydrocarbon sulfonates are the preferred collectors for glaserite and when they or the sulfates are used, the amount required to yield a highly selective float can range from about 10 to about 1,000 grams per ton of ore solids processed, preferably from about 50 to about grams per ton.

To promote the collector reagents of this invention, there may also be present in the flotation system secondary and tertiary alcohols or mixtures thereof. The nature and the quantity of the secondary or tertiary alcohol is not narrowly critical and there may be mentioned, as illustrations of useful secondary and tertiary alcohols; methylethyl carbinol, i butyl alcohol, trimethyl carbinol, 2,4-dimethyl-3-ethyl-3'hexanol, methyl amyl alcohol, diisobutyl carbinol, 2,6,8-trimethyl-4-nonanol, secondary amyl alcohol, tertiary amyl alcohol, methyl isobutyl carbinol and like secondary and tertiary alcohols. When used as a promoter, the secondary or tertiary alcohols are normally present in an amount of from about 50 to about 150 or more grams per-ton of ore solids processed.

The equipment and procedures in the flotation separation of glaserite from salt systems using the collectors of this invention are fairly conventional. There may be used, for instance, Denver and Wemco flotation systems, and like flotation systems which introduce air bubbles through the impeller or disperse air provided from an independent source.

For maximum efficiency in the separation of glaserite from the mineral ore processed, it is preferred to grind the ore to 30 Tyler Mesh or less and to operate the flotation separation at a 20 to 30 percent solids concentration, although solids concentrations up to 40 percent or more can be conveniently handled. Although flotation can be conveniently conducted in the presence of a mother liquor, it has been found that separation of the salts from the mother liquor by decantation, centrifugation and like methods, followed by washing the crystallites with a pure brine saturated with respect to the salts to remove bitterns and entrained organics, greatly enhances the cleanliness of the cuts obtained. Washing of the salts to remove bitterns will improve the beneficiations obtained and the number of flotation stages required to obtain a glaserite of high purity can be reduced.

The following examples demonstrate the flotation separation of glaserite from glaserite-sodium chloride-potassium chloride or systems which contain other salts, such as borax and teepelite, found in a harvest from Searles Lake brine. It should be understood, however, that the invention is nowise limited to separation of glaserite from such salt systems but is applicable to the separation of glaserite from any salt system containing glaserite. 1n the examples all percentages are shown as weight percentages unless otherwise indicated.

EXAMPLE 1 A salt harvest containing glaserite, halite and minor amounts of other salts were ground to 42 mesh and washed with a brine saturated with respect to the deposited salts. The ground salts were then slurried in a brine saturated with respect to the salts in a concentration of about 25 percent solids in a Denver DR Cell. Sulfonated a-eicosene was added as the reagent in an amount equivalent to 40 grams per ton of salts. A rough or bulk flotation to extract most of the entrained glaserite and a cleaner flotation was used to obtain a more pure product. The rough flotation resulted in a yield of 84 percent glaserite from the salt complex while the yield in the cleaner flotation was 96 percent. The overall yield, less entrainment, was 80.5 percent. Table 1 lists the composition of the feed, the composition of the rougher float, the composition of the cleaner float, the composition of the cleaner return, which was time controlled to fairly match the composition of the feed, as well as the composition of the tails, which were discarded.

The procedure of example 1 was repeated using a slightly different salt complex, which was substantially a pure glaserite-halite mixture. This study resulted in a rough yield of 88 percent glaserite, a cleaner yield of 94.5 percent glaserite and an overall yield, less scavenger, of 75 percent glaserite. The composition of the feed, rougher float, cleaner float, cleaner return and tails are shown in Table 11 TABLE II Glaserite NaCl 7:

Feed 26.4 73.6 Rougher 6O 40 Cleaner 82.0 18.0 Cleaner return 24.2 74.8 Tails 5.0 95.0

EXAMPLE 3 Following the procedure set forth in example 1, a salt mixture was subjected to froth flotation to extract glaserite using as the flotation reagent sulfosuccinate in an amount equivalent to 600 grams per ton of salt solids. The analysis of the system before and after the flotation is shown in Table [11. The flotation yield was 89.8 percent glasertie, entrainment free.

TABLE Ill 1(% Na% C 7: Cl% SO,% 8,0

Feed (dry) 35.29

6.92 27.79 Float (wet) 33.43

8.00 0.64 0.58 54.68 0.68 Float (6% cm.)

33.09 6.49 54.18 Feed brine 3.43

EXAMPLE 4 A salt sample ground to between 60 and Tyler Mesh was subject to flotation following the procedure set forth in example 1, using as the flotation reagent a tall oil fatty acid in a concentration equivalent to 600 grams per ton of salt solids. After a flotation time of 15 minutes, there was obtained a float which was 67.5 percent glaserite, entrainment free, at a purity of 94.4 percent. The analysis of the system subject to froth flotation is shown in Table IV.

TABLE IV 1(% Na% CO Cl% 80 B O Feed (dry) 35.29

6.92 57.79 Float (wet) 33.51

7.29 0.75 0.39 54.68 0.15 Float ta (6.5% ent.)

33.29 6.52 54.51 Feed brine 3.42

EXAMPLE 5 Using the procedure set forth in example 1, a salt mixture having a particle size between 1 50 and +200 mesh Tyler, was subject to froth flotation using as the collector reagent Petronate HL, a sulfonated hydrocarbon fraction have molecular weight range from 440 to 470 and an empirical formula of c,,H, s0,Na and manufactured by the Sonnebom Division of Witco Chemical Company, in a concentration equivalent to 600 grams per ton of salt solids. The float yield was 60.5 percent glaserite, entrainment free. The analysis of the system is shown in Table V.

A salt mixture, having a particle size from 60 to +80 mesh Tyler, was subjected to froth flotation to recover glaserite using a-eicosene at a concentration of 600 grams per ton. The flotation yielded 91.7 percent glaserite, entrainment free, and

the analysis of the system is shown in Table VI.

TABLE VI 10% Na% co,% Cl% soy. 8,0

Feed (dry) 35.29

6.92 57.79 Float (wet) 34.69

7.59 0.51 .35 55.60 Float (5% ent.)

33.86 6.64 55.46 Feed brine 3.48

EXAMPLE 7 A crude salt sample was treated in the manner set forth in example 1, using as the flotation reagent for glaserite Petronate WP, an anionic alkyl naphthalene sulfonate manufactured by the Sonnebom Division of Witco Chemical Company. There was obtained a glaserite yield in the float of 92 percent.

EXAMPLE 8 EXAMPLE 9 The procedure of example i was repeated on a crude salt sample, having a particle size from -l00 to +200 mesh Tyler, using as the flotation collector for glaserite a sulfonated castor oil acid. The float yielded 87 percent glaserite, entrainment free.

EXAMPLE 10 The procedure of example 9 was repeated except there was used as the flotation reagent sulfonated a-hexadecene. The flotation yielded 97 percent of the glaserite, entrainment free.

What is claimed is:

1. A process for the separation of glaserite from a grouping of mineral salts comprising salts formed from the species potassium, sodium, carbonate, chloride, sulfate and borate which comprises subjecting said grouping of mineral salts to froth flotation to obtain a float containing predominately glaserite in an aqueous media in the presence of a sulfonated hydrocarbon containing from about 16 to about 30 carbon atoms and selected from the group consisting of sulfonated a olefins and alkane sulfonates, said sulfonated hydrocarbon being present in the amount equivalent to about 10 to about 1,000 grams per ton of salt solids processed.

2. A process as claimed in claim 1 in which the sulfonated hydrocarbon is sulfonated a-eicosene or sulfonated a-hexadecene.

3. A process as claimed in claim 1 in which the sulfonated hydrocarbon has the empirical formula C ll So Na.

4. A process as claimed in claim 1 in which the sulfonated hydrocarbon is an anionic alkyl naphthalene sulfonate.

( -W3" umncn s m'ms PATENT OFFICE CEIVITIFICATE ()F CORRECTION Patent No. 3,675,773 Dated July 1.1, 197 2 Inventor(s) Elie M. Chemtob; William R. White; Rolando V. Marcote It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In the specification, page 7, line 22. Col. 3,- line 60 "glasertie" should read glaserite p In the Patent portions of Tables III, IV, V and VI were erroneously tabulated as per the attached.

4 As 1 cr Patrnt. Should read as per Specification:

(101. 3, lines 65-74 Page 7, lines 24"28 K% N i a nu: III

Fe:d(dry) 35.29 i W- 692 Iced (dry) 35.29 6.92 Fkgagxgwel) 33.43 Hut (wt) 33.63 8.00 m "on (61 cut.) 33.09 6.49

3109 Q49 1 h 1 Feed bring 34 3A] 11.10

Continued on next page b (IERTIFICATE OF CORRECTION Patent No. "3,675,773 Dated July 11, 1972 Inventor(s) Elie M. Chemtob; William R. White; Rolando V. Marcote It is certified that error appears in the bove-identified patent and that said Letters Patent are hereby corrected as shown below:

As per Patent: Should read as per Specification:

Col. 4, lines 13-21 Page 8, lines ll-l m Nal: nu: xv

KL A $17. EW" 3519 ry) 15.29 6.92 rffgwu) 33.51 flout (v.1) 33.51 1.29 (65% cm) Float (6.51. we.) 33.29 6.52 Feed 13am 3 72 1' n.a9 11.89

Col. 4, lines 38 47 Page 9, lines 26 KZ: Nai nau: v

40 Fccd(dry) 35,29 E 1i V6.92 rm: (dry) v.29 6.92 H03! ct) 33.16

- Floal (6.9% cm.) 3279 n: 6.92 cut.) 32.19 6.63 Q4} Feed brine 3.75 11.63

Feed brine 3.75

Col. 4, lines 58-66 Page 9, lines 14-18 K't NI; TABLE VI 60 Feedhky) 5.29 L

n6.92 Pm! (1) 15.29 0.92 ,39 (m) .69 1.59 Float (5% um) I! 5 3186 664 I n 1. cut a: as 6.66 m "T 45 rm: brhu a." 11.9;

Signed and sealed this 6th day of February 1973.

(SEAL) Attest:

EDWARD M PLETCHER ,JR ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents 

2. A process as claimed in claim 1 in which the sulfonated hydrocarbon is sulfonated Alpha -eicosene or sulfonated Alpha -hexadecene.
 3. A process as claimed in claim 1 in which the sulfonated hydrocarbon has the empirical formula C26H42SO3Na.
 4. A process as claimed in claim 1 in which the sulfonated hydrocarbon is an anionic alkyl naphthalene sulfonate. 